Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 1 | /* |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 2 | * Compressed RAM block device |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 3 | * |
Nitin Gupta | 1130ebb | 2010-01-28 21:21:35 +0530 | [diff] [blame] | 4 | * Copyright (C) 2008, 2009, 2010 Nitin Gupta |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 5 | * |
| 6 | * This code is released using a dual license strategy: BSD/GPL |
| 7 | * You can choose the licence that better fits your requirements. |
| 8 | * |
| 9 | * Released under the terms of 3-clause BSD License |
| 10 | * Released under the terms of GNU General Public License Version 2.0 |
| 11 | * |
| 12 | * Project home: http://compcache.googlecode.com |
| 13 | */ |
| 14 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 15 | #define KMSG_COMPONENT "zram" |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 16 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
| 17 | |
Robert Jennings | b1f5b81 | 2011-01-28 08:59:26 -0600 | [diff] [blame] | 18 | #ifdef CONFIG_ZRAM_DEBUG |
| 19 | #define DEBUG |
| 20 | #endif |
| 21 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 22 | #include <linux/module.h> |
| 23 | #include <linux/kernel.h> |
Randy Dunlap | 8946a08 | 2010-06-23 20:27:09 -0700 | [diff] [blame] | 24 | #include <linux/bio.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 25 | #include <linux/bitops.h> |
| 26 | #include <linux/blkdev.h> |
| 27 | #include <linux/buffer_head.h> |
| 28 | #include <linux/device.h> |
| 29 | #include <linux/genhd.h> |
| 30 | #include <linux/highmem.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 31 | #include <linux/slab.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 32 | #include <linux/lzo.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 33 | #include <linux/string.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 34 | #include <linux/vmalloc.h> |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 35 | |
Nitin Gupta | 16a4bfb | 2010-06-01 13:31:24 +0530 | [diff] [blame] | 36 | #include "zram_drv.h" |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 37 | |
| 38 | /* Globals */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 39 | static int zram_major; |
Jiang Liu | 0f0e3ba | 2013-06-07 00:07:29 +0800 | [diff] [blame] | 40 | static struct zram *zram_devices; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 41 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 42 | /* Module params (documentation at end) */ |
Davidlohr Bueso | ca3d70b | 2013-01-01 21:24:13 -0800 | [diff] [blame] | 43 | static unsigned int num_devices = 1; |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 44 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 45 | static inline struct zram *dev_to_zram(struct device *dev) |
| 46 | { |
| 47 | return (struct zram *)dev_to_disk(dev)->private_data; |
| 48 | } |
| 49 | |
| 50 | static ssize_t disksize_show(struct device *dev, |
| 51 | struct device_attribute *attr, char *buf) |
| 52 | { |
| 53 | struct zram *zram = dev_to_zram(dev); |
| 54 | |
| 55 | return sprintf(buf, "%llu\n", zram->disksize); |
| 56 | } |
| 57 | |
| 58 | static ssize_t initstate_show(struct device *dev, |
| 59 | struct device_attribute *attr, char *buf) |
| 60 | { |
| 61 | struct zram *zram = dev_to_zram(dev); |
| 62 | |
| 63 | return sprintf(buf, "%u\n", zram->init_done); |
| 64 | } |
| 65 | |
| 66 | static ssize_t num_reads_show(struct device *dev, |
| 67 | struct device_attribute *attr, char *buf) |
| 68 | { |
| 69 | struct zram *zram = dev_to_zram(dev); |
| 70 | |
| 71 | return sprintf(buf, "%llu\n", |
| 72 | (u64)atomic64_read(&zram->stats.num_reads)); |
| 73 | } |
| 74 | |
| 75 | static ssize_t num_writes_show(struct device *dev, |
| 76 | struct device_attribute *attr, char *buf) |
| 77 | { |
| 78 | struct zram *zram = dev_to_zram(dev); |
| 79 | |
| 80 | return sprintf(buf, "%llu\n", |
| 81 | (u64)atomic64_read(&zram->stats.num_writes)); |
| 82 | } |
| 83 | |
| 84 | static ssize_t invalid_io_show(struct device *dev, |
| 85 | struct device_attribute *attr, char *buf) |
| 86 | { |
| 87 | struct zram *zram = dev_to_zram(dev); |
| 88 | |
| 89 | return sprintf(buf, "%llu\n", |
| 90 | (u64)atomic64_read(&zram->stats.invalid_io)); |
| 91 | } |
| 92 | |
| 93 | static ssize_t notify_free_show(struct device *dev, |
| 94 | struct device_attribute *attr, char *buf) |
| 95 | { |
| 96 | struct zram *zram = dev_to_zram(dev); |
| 97 | |
| 98 | return sprintf(buf, "%llu\n", |
| 99 | (u64)atomic64_read(&zram->stats.notify_free)); |
| 100 | } |
| 101 | |
| 102 | static ssize_t zero_pages_show(struct device *dev, |
| 103 | struct device_attribute *attr, char *buf) |
| 104 | { |
| 105 | struct zram *zram = dev_to_zram(dev); |
| 106 | |
| 107 | return sprintf(buf, "%u\n", zram->stats.pages_zero); |
| 108 | } |
| 109 | |
| 110 | static ssize_t orig_data_size_show(struct device *dev, |
| 111 | struct device_attribute *attr, char *buf) |
| 112 | { |
| 113 | struct zram *zram = dev_to_zram(dev); |
| 114 | |
| 115 | return sprintf(buf, "%llu\n", |
| 116 | (u64)(zram->stats.pages_stored) << PAGE_SHIFT); |
| 117 | } |
| 118 | |
| 119 | static ssize_t compr_data_size_show(struct device *dev, |
| 120 | struct device_attribute *attr, char *buf) |
| 121 | { |
| 122 | struct zram *zram = dev_to_zram(dev); |
| 123 | |
| 124 | return sprintf(buf, "%llu\n", |
| 125 | (u64)atomic64_read(&zram->stats.compr_size)); |
| 126 | } |
| 127 | |
| 128 | static ssize_t mem_used_total_show(struct device *dev, |
| 129 | struct device_attribute *attr, char *buf) |
| 130 | { |
| 131 | u64 val = 0; |
| 132 | struct zram *zram = dev_to_zram(dev); |
| 133 | struct zram_meta *meta = zram->meta; |
| 134 | |
| 135 | down_read(&zram->init_lock); |
| 136 | if (zram->init_done) |
| 137 | val = zs_get_total_size_bytes(meta->mem_pool); |
| 138 | up_read(&zram->init_lock); |
| 139 | |
| 140 | return sprintf(buf, "%llu\n", val); |
| 141 | } |
| 142 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 143 | static int zram_test_flag(struct zram_meta *meta, u32 index, |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 144 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 145 | { |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 146 | return meta->table[index].flags & BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 147 | } |
| 148 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 149 | static void zram_set_flag(struct zram_meta *meta, u32 index, |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 150 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 151 | { |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 152 | meta->table[index].flags |= BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 153 | } |
| 154 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 155 | static void zram_clear_flag(struct zram_meta *meta, u32 index, |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 156 | enum zram_pageflags flag) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 157 | { |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 158 | meta->table[index].flags &= ~BIT(flag); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 159 | } |
| 160 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 161 | static inline int is_partial_io(struct bio_vec *bvec) |
| 162 | { |
| 163 | return bvec->bv_len != PAGE_SIZE; |
| 164 | } |
| 165 | |
| 166 | /* |
| 167 | * Check if request is within bounds and aligned on zram logical blocks. |
| 168 | */ |
| 169 | static inline int valid_io_request(struct zram *zram, struct bio *bio) |
| 170 | { |
| 171 | u64 start, end, bound; |
Kumar Gaurav | a539c72 | 2013-08-08 23:53:24 +0530 | [diff] [blame^] | 172 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 173 | /* unaligned request */ |
| 174 | if (unlikely(bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1))) |
| 175 | return 0; |
| 176 | if (unlikely(bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1))) |
| 177 | return 0; |
| 178 | |
| 179 | start = bio->bi_sector; |
| 180 | end = start + (bio->bi_size >> SECTOR_SHIFT); |
| 181 | bound = zram->disksize >> SECTOR_SHIFT; |
| 182 | /* out of range range */ |
Sergey Senozhatsky | 75c7caf | 2013-06-22 17:21:00 +0300 | [diff] [blame] | 183 | if (unlikely(start >= bound || end > bound || start > end)) |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 184 | return 0; |
| 185 | |
| 186 | /* I/O request is valid */ |
| 187 | return 1; |
| 188 | } |
| 189 | |
| 190 | static void zram_meta_free(struct zram_meta *meta) |
| 191 | { |
| 192 | zs_destroy_pool(meta->mem_pool); |
| 193 | kfree(meta->compress_workmem); |
| 194 | free_pages((unsigned long)meta->compress_buffer, 1); |
| 195 | vfree(meta->table); |
| 196 | kfree(meta); |
| 197 | } |
| 198 | |
| 199 | static struct zram_meta *zram_meta_alloc(u64 disksize) |
| 200 | { |
| 201 | size_t num_pages; |
| 202 | struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL); |
| 203 | if (!meta) |
| 204 | goto out; |
| 205 | |
| 206 | meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); |
| 207 | if (!meta->compress_workmem) |
| 208 | goto free_meta; |
| 209 | |
| 210 | meta->compress_buffer = |
| 211 | (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1); |
| 212 | if (!meta->compress_buffer) { |
| 213 | pr_err("Error allocating compressor buffer space\n"); |
| 214 | goto free_workmem; |
| 215 | } |
| 216 | |
| 217 | num_pages = disksize >> PAGE_SHIFT; |
| 218 | meta->table = vzalloc(num_pages * sizeof(*meta->table)); |
| 219 | if (!meta->table) { |
| 220 | pr_err("Error allocating zram address table\n"); |
| 221 | goto free_buffer; |
| 222 | } |
| 223 | |
| 224 | meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); |
| 225 | if (!meta->mem_pool) { |
| 226 | pr_err("Error creating memory pool\n"); |
| 227 | goto free_table; |
| 228 | } |
| 229 | |
| 230 | return meta; |
| 231 | |
| 232 | free_table: |
| 233 | vfree(meta->table); |
| 234 | free_buffer: |
| 235 | free_pages((unsigned long)meta->compress_buffer, 1); |
| 236 | free_workmem: |
| 237 | kfree(meta->compress_workmem); |
| 238 | free_meta: |
| 239 | kfree(meta); |
| 240 | meta = NULL; |
| 241 | out: |
| 242 | return meta; |
| 243 | } |
| 244 | |
| 245 | static void update_position(u32 *index, int *offset, struct bio_vec *bvec) |
| 246 | { |
| 247 | if (*offset + bvec->bv_len >= PAGE_SIZE) |
| 248 | (*index)++; |
| 249 | *offset = (*offset + bvec->bv_len) % PAGE_SIZE; |
| 250 | } |
| 251 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 252 | static int page_zero_filled(void *ptr) |
| 253 | { |
| 254 | unsigned int pos; |
| 255 | unsigned long *page; |
| 256 | |
| 257 | page = (unsigned long *)ptr; |
| 258 | |
| 259 | for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) { |
| 260 | if (page[pos]) |
| 261 | return 0; |
| 262 | } |
| 263 | |
| 264 | return 1; |
| 265 | } |
| 266 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 267 | static void handle_zero_page(struct bio_vec *bvec) |
| 268 | { |
| 269 | struct page *page = bvec->bv_page; |
| 270 | void *user_mem; |
| 271 | |
| 272 | user_mem = kmap_atomic(page); |
| 273 | if (is_partial_io(bvec)) |
| 274 | memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); |
| 275 | else |
| 276 | clear_page(user_mem); |
| 277 | kunmap_atomic(user_mem); |
| 278 | |
| 279 | flush_dcache_page(page); |
| 280 | } |
| 281 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 282 | static void zram_free_page(struct zram *zram, size_t index) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 283 | { |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 284 | struct zram_meta *meta = zram->meta; |
| 285 | unsigned long handle = meta->table[index].handle; |
| 286 | u16 size = meta->table[index].size; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 287 | |
Nitin Gupta | fd1a30d | 2012-01-09 16:51:59 -0600 | [diff] [blame] | 288 | if (unlikely(!handle)) { |
Nitin Gupta | 2e88228 | 2010-01-28 21:13:41 +0530 | [diff] [blame] | 289 | /* |
| 290 | * No memory is allocated for zero filled pages. |
| 291 | * Simply clear zero page flag. |
| 292 | */ |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 293 | if (zram_test_flag(meta, index, ZRAM_ZERO)) { |
| 294 | zram_clear_flag(meta, index, ZRAM_ZERO); |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 295 | zram->stats.pages_zero--; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 296 | } |
| 297 | return; |
| 298 | } |
| 299 | |
Minchan Kim | 130f315 | 2012-06-08 15:39:27 +0900 | [diff] [blame] | 300 | if (unlikely(size > max_zpage_size)) |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 301 | zram->stats.bad_compress--; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 302 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 303 | zs_free(meta->mem_pool, handle); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 304 | |
Minchan Kim | 130f315 | 2012-06-08 15:39:27 +0900 | [diff] [blame] | 305 | if (size <= PAGE_SIZE / 2) |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 306 | zram->stats.good_compress--; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 307 | |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 308 | atomic64_sub(meta->table[index].size, &zram->stats.compr_size); |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 309 | zram->stats.pages_stored--; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 310 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 311 | meta->table[index].handle = 0; |
| 312 | meta->table[index].size = 0; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 313 | } |
| 314 | |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 315 | static int zram_decompress_page(struct zram *zram, char *mem, u32 index) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 316 | { |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 317 | int ret = LZO_E_OK; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 318 | size_t clen = PAGE_SIZE; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 319 | unsigned char *cmem; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 320 | struct zram_meta *meta = zram->meta; |
| 321 | unsigned long handle = meta->table[index].handle; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 322 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 323 | if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) { |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 324 | clear_page(mem); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 325 | return 0; |
| 326 | } |
| 327 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 328 | cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO); |
| 329 | if (meta->table[index].size == PAGE_SIZE) |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 330 | copy_page(mem, cmem); |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 331 | else |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 332 | ret = lzo1x_decompress_safe(cmem, meta->table[index].size, |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 333 | mem, &clen); |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 334 | zs_unmap_object(meta->mem_pool, handle); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 335 | |
| 336 | /* Should NEVER happen. Return bio error if it does. */ |
| 337 | if (unlikely(ret != LZO_E_OK)) { |
| 338 | pr_err("Decompression failed! err=%d, page=%u\n", ret, index); |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 339 | atomic64_inc(&zram->stats.failed_reads); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 340 | return ret; |
| 341 | } |
| 342 | |
| 343 | return 0; |
| 344 | } |
| 345 | |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 346 | static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, |
| 347 | u32 index, int offset, struct bio *bio) |
| 348 | { |
| 349 | int ret; |
| 350 | struct page *page; |
| 351 | unsigned char *user_mem, *uncmem = NULL; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 352 | struct zram_meta *meta = zram->meta; |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 353 | page = bvec->bv_page; |
| 354 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 355 | if (unlikely(!meta->table[index].handle) || |
| 356 | zram_test_flag(meta, index, ZRAM_ZERO)) { |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 357 | handle_zero_page(bvec); |
| 358 | return 0; |
| 359 | } |
| 360 | |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 361 | if (is_partial_io(bvec)) |
| 362 | /* Use a temporary buffer to decompress the page */ |
Minchan Kim | 7e5a510 | 2013-01-30 11:41:39 +0900 | [diff] [blame] | 363 | uncmem = kmalloc(PAGE_SIZE, GFP_NOIO); |
| 364 | |
| 365 | user_mem = kmap_atomic(page); |
| 366 | if (!is_partial_io(bvec)) |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 367 | uncmem = user_mem; |
| 368 | |
| 369 | if (!uncmem) { |
| 370 | pr_info("Unable to allocate temp memory\n"); |
| 371 | ret = -ENOMEM; |
| 372 | goto out_cleanup; |
| 373 | } |
| 374 | |
| 375 | ret = zram_decompress_page(zram, uncmem, index); |
| 376 | /* Should NEVER happen. Return bio error if it does. */ |
Wanpeng Li | 25eeb66 | 2013-03-13 15:06:16 +0800 | [diff] [blame] | 377 | if (unlikely(ret != LZO_E_OK)) |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 378 | goto out_cleanup; |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 379 | |
| 380 | if (is_partial_io(bvec)) |
| 381 | memcpy(user_mem + bvec->bv_offset, uncmem + offset, |
| 382 | bvec->bv_len); |
| 383 | |
| 384 | flush_dcache_page(page); |
| 385 | ret = 0; |
| 386 | out_cleanup: |
| 387 | kunmap_atomic(user_mem); |
| 388 | if (is_partial_io(bvec)) |
| 389 | kfree(uncmem); |
| 390 | return ret; |
| 391 | } |
| 392 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 393 | static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, |
| 394 | int offset) |
| 395 | { |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 396 | int ret = 0; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 397 | size_t clen; |
Minchan Kim | c234434 | 2012-06-08 15:39:25 +0900 | [diff] [blame] | 398 | unsigned long handle; |
Minchan Kim | 130f315 | 2012-06-08 15:39:27 +0900 | [diff] [blame] | 399 | struct page *page; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 400 | unsigned char *user_mem, *cmem, *src, *uncmem = NULL; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 401 | struct zram_meta *meta = zram->meta; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 402 | |
| 403 | page = bvec->bv_page; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 404 | src = meta->compress_buffer; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 405 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 406 | if (is_partial_io(bvec)) { |
| 407 | /* |
| 408 | * This is a partial IO. We need to read the full page |
| 409 | * before to write the changes. |
| 410 | */ |
Minchan Kim | 7e5a510 | 2013-01-30 11:41:39 +0900 | [diff] [blame] | 411 | uncmem = kmalloc(PAGE_SIZE, GFP_NOIO); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 412 | if (!uncmem) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 413 | ret = -ENOMEM; |
| 414 | goto out; |
| 415 | } |
Sergey Senozhatsky | 37b51fd | 2012-10-30 22:40:23 +0300 | [diff] [blame] | 416 | ret = zram_decompress_page(zram, uncmem, index); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 417 | if (ret) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 418 | goto out; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 419 | } |
| 420 | |
Cong Wang | ba82fe2 | 2011-11-25 23:14:25 +0800 | [diff] [blame] | 421 | user_mem = kmap_atomic(page); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 422 | |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 423 | if (is_partial_io(bvec)) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 424 | memcpy(uncmem + offset, user_mem + bvec->bv_offset, |
| 425 | bvec->bv_len); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 426 | kunmap_atomic(user_mem); |
| 427 | user_mem = NULL; |
| 428 | } else { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 429 | uncmem = user_mem; |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 430 | } |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 431 | |
| 432 | if (page_zero_filled(uncmem)) { |
Cong Wang | ba82fe2 | 2011-11-25 23:14:25 +0800 | [diff] [blame] | 433 | kunmap_atomic(user_mem); |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 434 | /* Free memory associated with this sector now. */ |
| 435 | zram_free_page(zram, index); |
| 436 | |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 437 | zram->stats.pages_zero++; |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 438 | zram_set_flag(meta, index, ZRAM_ZERO); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 439 | ret = 0; |
| 440 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 441 | } |
| 442 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 443 | ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen, |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 444 | meta->compress_workmem); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 445 | |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 446 | if (!is_partial_io(bvec)) { |
| 447 | kunmap_atomic(user_mem); |
| 448 | user_mem = NULL; |
| 449 | uncmem = NULL; |
| 450 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 451 | |
| 452 | if (unlikely(ret != LZO_E_OK)) { |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 453 | pr_err("Compression failed! err=%d\n", ret); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 454 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 455 | } |
| 456 | |
Nitin Gupta | c8f2f0d | 2012-10-10 17:42:18 -0700 | [diff] [blame] | 457 | if (unlikely(clen > max_zpage_size)) { |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 458 | zram->stats.bad_compress++; |
Nitin Gupta | c8f2f0d | 2012-10-10 17:42:18 -0700 | [diff] [blame] | 459 | clen = PAGE_SIZE; |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 460 | src = NULL; |
| 461 | if (is_partial_io(bvec)) |
| 462 | src = uncmem; |
Nitin Gupta | c8f2f0d | 2012-10-10 17:42:18 -0700 | [diff] [blame] | 463 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 464 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 465 | handle = zs_malloc(meta->mem_pool, clen); |
Nitin Gupta | fd1a30d | 2012-01-09 16:51:59 -0600 | [diff] [blame] | 466 | if (!handle) { |
Marlies Ruck | 596b3dd | 2013-05-16 14:30:39 -0400 | [diff] [blame] | 467 | pr_info("Error allocating memory for compressed page: %u, size=%zu\n", |
| 468 | index, clen); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 469 | ret = -ENOMEM; |
| 470 | goto out; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 471 | } |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 472 | cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 473 | |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 474 | if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) { |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 475 | src = kmap_atomic(page); |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 476 | copy_page(cmem, src); |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 477 | kunmap_atomic(src); |
Jiang Liu | 42e99bd | 2013-06-07 00:07:30 +0800 | [diff] [blame] | 478 | } else { |
| 479 | memcpy(cmem, src, clen); |
| 480 | } |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 481 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 482 | zs_unmap_object(meta->mem_pool, handle); |
Nitin Gupta | fd1a30d | 2012-01-09 16:51:59 -0600 | [diff] [blame] | 483 | |
Sunghan Suh | f40ac2a | 2013-07-03 20:10:05 +0900 | [diff] [blame] | 484 | /* |
| 485 | * Free memory associated with this sector |
| 486 | * before overwriting unused sectors. |
| 487 | */ |
| 488 | zram_free_page(zram, index); |
| 489 | |
Minchan Kim | 8b3cc3e | 2013-02-06 08:48:53 +0900 | [diff] [blame] | 490 | meta->table[index].handle = handle; |
| 491 | meta->table[index].size = clen; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 492 | |
| 493 | /* Update stats */ |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 494 | atomic64_add(clen, &zram->stats.compr_size); |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 495 | zram->stats.pages_stored++; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 496 | if (clen <= PAGE_SIZE / 2) |
Davidlohr Bueso | d178a07 | 2013-01-01 21:24:29 -0800 | [diff] [blame] | 497 | zram->stats.good_compress++; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 498 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 499 | out: |
Nitin Gupta | 397c606 | 2013-01-02 08:53:41 -0800 | [diff] [blame] | 500 | if (is_partial_io(bvec)) |
| 501 | kfree(uncmem); |
| 502 | |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 503 | if (ret) |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 504 | atomic64_inc(&zram->stats.failed_writes); |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 505 | return ret; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 506 | } |
| 507 | |
| 508 | static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 509 | int offset, struct bio *bio, int rw) |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 510 | { |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 511 | int ret; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 512 | |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 513 | if (rw == READ) { |
| 514 | down_read(&zram->lock); |
| 515 | ret = zram_bvec_read(zram, bvec, index, offset, bio); |
| 516 | up_read(&zram->lock); |
| 517 | } else { |
| 518 | down_write(&zram->lock); |
| 519 | ret = zram_bvec_write(zram, bvec, index, offset); |
| 520 | up_write(&zram->lock); |
| 521 | } |
| 522 | |
| 523 | return ret; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 524 | } |
| 525 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 526 | static void zram_reset_device(struct zram *zram) |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 527 | { |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 528 | size_t index; |
| 529 | struct zram_meta *meta; |
| 530 | |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 531 | down_write(&zram->init_lock); |
| 532 | if (!zram->init_done) { |
| 533 | up_write(&zram->init_lock); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 534 | return; |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 535 | } |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 536 | |
| 537 | meta = zram->meta; |
| 538 | zram->init_done = 0; |
| 539 | |
| 540 | /* Free all pages that are still in this zram device */ |
| 541 | for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { |
| 542 | unsigned long handle = meta->table[index].handle; |
| 543 | if (!handle) |
| 544 | continue; |
| 545 | |
| 546 | zs_free(meta->mem_pool, handle); |
| 547 | } |
| 548 | |
| 549 | zram_meta_free(zram->meta); |
| 550 | zram->meta = NULL; |
| 551 | /* Reset stats */ |
| 552 | memset(&zram->stats, 0, sizeof(zram->stats)); |
| 553 | |
| 554 | zram->disksize = 0; |
| 555 | set_capacity(zram->disk, 0); |
Sergey Senozhatsky | 644d478 | 2013-06-26 15:28:39 +0300 | [diff] [blame] | 556 | up_write(&zram->init_lock); |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 557 | } |
| 558 | |
| 559 | static void zram_init_device(struct zram *zram, struct zram_meta *meta) |
| 560 | { |
| 561 | if (zram->disksize > 2 * (totalram_pages << PAGE_SHIFT)) { |
| 562 | pr_info( |
| 563 | "There is little point creating a zram of greater than " |
| 564 | "twice the size of memory since we expect a 2:1 compression " |
| 565 | "ratio. Note that zram uses about 0.1%% of the size of " |
| 566 | "the disk when not in use so a huge zram is " |
| 567 | "wasteful.\n" |
| 568 | "\tMemory Size: %lu kB\n" |
| 569 | "\tSize you selected: %llu kB\n" |
| 570 | "Continuing anyway ...\n", |
| 571 | (totalram_pages << PAGE_SHIFT) >> 10, zram->disksize >> 10 |
| 572 | ); |
| 573 | } |
| 574 | |
| 575 | /* zram devices sort of resembles non-rotational disks */ |
| 576 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); |
| 577 | |
| 578 | zram->meta = meta; |
| 579 | zram->init_done = 1; |
| 580 | |
| 581 | pr_debug("Initialization done!\n"); |
| 582 | } |
| 583 | |
| 584 | static ssize_t disksize_store(struct device *dev, |
| 585 | struct device_attribute *attr, const char *buf, size_t len) |
| 586 | { |
| 587 | u64 disksize; |
| 588 | struct zram_meta *meta; |
| 589 | struct zram *zram = dev_to_zram(dev); |
| 590 | |
| 591 | disksize = memparse(buf, NULL); |
| 592 | if (!disksize) |
| 593 | return -EINVAL; |
| 594 | |
| 595 | disksize = PAGE_ALIGN(disksize); |
| 596 | meta = zram_meta_alloc(disksize); |
| 597 | down_write(&zram->init_lock); |
| 598 | if (zram->init_done) { |
| 599 | up_write(&zram->init_lock); |
| 600 | zram_meta_free(meta); |
| 601 | pr_info("Cannot change disksize for initialized device\n"); |
| 602 | return -EBUSY; |
| 603 | } |
| 604 | |
| 605 | zram->disksize = disksize; |
| 606 | set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); |
| 607 | zram_init_device(zram, meta); |
| 608 | up_write(&zram->init_lock); |
| 609 | |
| 610 | return len; |
| 611 | } |
| 612 | |
| 613 | static ssize_t reset_store(struct device *dev, |
| 614 | struct device_attribute *attr, const char *buf, size_t len) |
| 615 | { |
| 616 | int ret; |
| 617 | unsigned short do_reset; |
| 618 | struct zram *zram; |
| 619 | struct block_device *bdev; |
| 620 | |
| 621 | zram = dev_to_zram(dev); |
| 622 | bdev = bdget_disk(zram->disk, 0); |
| 623 | |
| 624 | /* Do not reset an active device! */ |
| 625 | if (bdev->bd_holders) |
| 626 | return -EBUSY; |
| 627 | |
| 628 | ret = kstrtou16(buf, 10, &do_reset); |
| 629 | if (ret) |
| 630 | return ret; |
| 631 | |
| 632 | if (!do_reset) |
| 633 | return -EINVAL; |
| 634 | |
| 635 | /* Make sure all pending I/O is finished */ |
| 636 | if (bdev) |
| 637 | fsync_bdev(bdev); |
| 638 | |
| 639 | zram_reset_device(zram); |
| 640 | return len; |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 641 | } |
| 642 | |
| 643 | static void __zram_make_request(struct zram *zram, struct bio *bio, int rw) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 644 | { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 645 | int i, offset; |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 646 | u32 index; |
| 647 | struct bio_vec *bvec; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 648 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 649 | switch (rw) { |
| 650 | case READ: |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 651 | atomic64_inc(&zram->stats.num_reads); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 652 | break; |
| 653 | case WRITE: |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 654 | atomic64_inc(&zram->stats.num_writes); |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 655 | break; |
| 656 | } |
| 657 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 658 | index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 659 | offset = (bio->bi_sector & (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 660 | |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 661 | bio_for_each_segment(bvec, bio, i) { |
Jerome Marchand | 924bd88 | 2011-06-10 15:28:48 +0200 | [diff] [blame] | 662 | int max_transfer_size = PAGE_SIZE - offset; |
| 663 | |
| 664 | if (bvec->bv_len > max_transfer_size) { |
| 665 | /* |
| 666 | * zram_bvec_rw() can only make operation on a single |
| 667 | * zram page. Split the bio vector. |
| 668 | */ |
| 669 | struct bio_vec bv; |
| 670 | |
| 671 | bv.bv_page = bvec->bv_page; |
| 672 | bv.bv_len = max_transfer_size; |
| 673 | bv.bv_offset = bvec->bv_offset; |
| 674 | |
| 675 | if (zram_bvec_rw(zram, &bv, index, offset, bio, rw) < 0) |
| 676 | goto out; |
| 677 | |
| 678 | bv.bv_len = bvec->bv_len - max_transfer_size; |
| 679 | bv.bv_offset += max_transfer_size; |
| 680 | if (zram_bvec_rw(zram, &bv, index+1, 0, bio, rw) < 0) |
| 681 | goto out; |
| 682 | } else |
| 683 | if (zram_bvec_rw(zram, bvec, index, offset, bio, rw) |
| 684 | < 0) |
| 685 | goto out; |
| 686 | |
| 687 | update_position(&index, &offset, bvec); |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 688 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 689 | |
| 690 | set_bit(BIO_UPTODATE, &bio->bi_flags); |
| 691 | bio_endio(bio, 0); |
Nitin Gupta | 7d7854b | 2011-01-22 07:36:15 -0500 | [diff] [blame] | 692 | return; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 693 | |
| 694 | out: |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 695 | bio_io_error(bio); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 696 | } |
| 697 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 698 | /* |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 699 | * Handler function for all zram I/O requests. |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 700 | */ |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 701 | static void zram_make_request(struct request_queue *queue, struct bio *bio) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 702 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 703 | struct zram *zram = queue->queuedata; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 704 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 705 | down_read(&zram->init_lock); |
| 706 | if (unlikely(!zram->init_done)) |
Minchan Kim | 3de738c | 2013-01-30 11:41:41 +0900 | [diff] [blame] | 707 | goto error; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 708 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 709 | if (!valid_io_request(zram, bio)) { |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 710 | atomic64_inc(&zram->stats.invalid_io); |
Minchan Kim | 3de738c | 2013-01-30 11:41:41 +0900 | [diff] [blame] | 711 | goto error; |
Jerome Marchand | 6642a67 | 2011-02-17 17:11:49 +0100 | [diff] [blame] | 712 | } |
| 713 | |
Jerome Marchand | 8c921b2 | 2011-06-10 15:28:47 +0200 | [diff] [blame] | 714 | __zram_make_request(zram, bio, bio_data_dir(bio)); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 715 | up_read(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 716 | |
Linus Torvalds | b4fdcb0 | 2011-11-04 17:06:58 -0700 | [diff] [blame] | 717 | return; |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 718 | |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 719 | error: |
Minchan Kim | 3de738c | 2013-01-30 11:41:41 +0900 | [diff] [blame] | 720 | up_read(&zram->init_lock); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 721 | bio_io_error(bio); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 722 | } |
| 723 | |
Nitin Gupta | 2ccbec0 | 2011-09-09 19:01:00 -0400 | [diff] [blame] | 724 | static void zram_slot_free_notify(struct block_device *bdev, |
| 725 | unsigned long index) |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 726 | { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 727 | struct zram *zram; |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 728 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 729 | zram = bdev->bd_disk->private_data; |
Jiang Liu | 57ab048 | 2013-06-07 00:07:23 +0800 | [diff] [blame] | 730 | down_write(&zram->lock); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 731 | zram_free_page(zram, index); |
Jiang Liu | 57ab048 | 2013-06-07 00:07:23 +0800 | [diff] [blame] | 732 | up_write(&zram->lock); |
Jiang Liu | da5cc7d | 2013-06-07 00:07:31 +0800 | [diff] [blame] | 733 | atomic64_inc(&zram->stats.notify_free); |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 734 | } |
| 735 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 736 | static const struct block_device_operations zram_devops = { |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 737 | .swap_slot_free_notify = zram_slot_free_notify, |
Nitin Gupta | 107c161 | 2010-05-17 11:02:44 +0530 | [diff] [blame] | 738 | .owner = THIS_MODULE |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 739 | }; |
| 740 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 741 | static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR, |
| 742 | disksize_show, disksize_store); |
| 743 | static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL); |
| 744 | static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store); |
| 745 | static DEVICE_ATTR(num_reads, S_IRUGO, num_reads_show, NULL); |
| 746 | static DEVICE_ATTR(num_writes, S_IRUGO, num_writes_show, NULL); |
| 747 | static DEVICE_ATTR(invalid_io, S_IRUGO, invalid_io_show, NULL); |
| 748 | static DEVICE_ATTR(notify_free, S_IRUGO, notify_free_show, NULL); |
| 749 | static DEVICE_ATTR(zero_pages, S_IRUGO, zero_pages_show, NULL); |
| 750 | static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL); |
| 751 | static DEVICE_ATTR(compr_data_size, S_IRUGO, compr_data_size_show, NULL); |
| 752 | static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL); |
| 753 | |
| 754 | static struct attribute *zram_disk_attrs[] = { |
| 755 | &dev_attr_disksize.attr, |
| 756 | &dev_attr_initstate.attr, |
| 757 | &dev_attr_reset.attr, |
| 758 | &dev_attr_num_reads.attr, |
| 759 | &dev_attr_num_writes.attr, |
| 760 | &dev_attr_invalid_io.attr, |
| 761 | &dev_attr_notify_free.attr, |
| 762 | &dev_attr_zero_pages.attr, |
| 763 | &dev_attr_orig_data_size.attr, |
| 764 | &dev_attr_compr_data_size.attr, |
| 765 | &dev_attr_mem_used_total.attr, |
| 766 | NULL, |
| 767 | }; |
| 768 | |
| 769 | static struct attribute_group zram_disk_attr_group = { |
| 770 | .attrs = zram_disk_attrs, |
| 771 | }; |
| 772 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 773 | static int create_device(struct zram *zram, int device_id) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 774 | { |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 775 | int ret = -ENOMEM; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 776 | |
Jerome Marchand | c5bde23 | 2011-06-10 15:28:49 +0200 | [diff] [blame] | 777 | init_rwsem(&zram->lock); |
Jerome Marchand | 0900bea | 2011-09-06 15:02:11 +0200 | [diff] [blame] | 778 | init_rwsem(&zram->init_lock); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 779 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 780 | zram->queue = blk_alloc_queue(GFP_KERNEL); |
| 781 | if (!zram->queue) { |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 782 | pr_err("Error allocating disk queue for device %d\n", |
| 783 | device_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 784 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 785 | } |
| 786 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 787 | blk_queue_make_request(zram->queue, zram_make_request); |
| 788 | zram->queue->queuedata = zram; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 789 | |
| 790 | /* gendisk structure */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 791 | zram->disk = alloc_disk(1); |
| 792 | if (!zram->disk) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 793 | pr_warn("Error allocating disk structure for device %d\n", |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 794 | device_id); |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 795 | goto out_free_queue; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 796 | } |
| 797 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 798 | zram->disk->major = zram_major; |
| 799 | zram->disk->first_minor = device_id; |
| 800 | zram->disk->fops = &zram_devops; |
| 801 | zram->disk->queue = zram->queue; |
| 802 | zram->disk->private_data = zram; |
| 803 | snprintf(zram->disk->disk_name, 16, "zram%d", device_id); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 804 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 805 | /* Actual capacity set using syfs (/sys/block/zram<id>/disksize */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 806 | set_capacity(zram->disk, 0); |
Nitin Gupta | 5d83d5a | 2010-01-28 21:13:39 +0530 | [diff] [blame] | 807 | |
Nitin Gupta | a1dd52a | 2010-06-01 13:31:23 +0530 | [diff] [blame] | 808 | /* |
| 809 | * To ensure that we always get PAGE_SIZE aligned |
| 810 | * and n*PAGE_SIZED sized I/O requests. |
| 811 | */ |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 812 | blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE); |
Robert Jennings | 7b19b8d | 2011-01-28 08:58:17 -0600 | [diff] [blame] | 813 | blk_queue_logical_block_size(zram->disk->queue, |
| 814 | ZRAM_LOGICAL_BLOCK_SIZE); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 815 | blk_queue_io_min(zram->disk->queue, PAGE_SIZE); |
| 816 | blk_queue_io_opt(zram->disk->queue, PAGE_SIZE); |
Nitin Gupta | 5d83d5a | 2010-01-28 21:13:39 +0530 | [diff] [blame] | 817 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 818 | add_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 819 | |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 820 | ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj, |
| 821 | &zram_disk_attr_group); |
| 822 | if (ret < 0) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 823 | pr_warn("Error creating sysfs group"); |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 824 | goto out_free_disk; |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 825 | } |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 826 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 827 | zram->init_done = 0; |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 828 | return 0; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 829 | |
Jiang Liu | 39a9b8a | 2013-06-07 00:07:24 +0800 | [diff] [blame] | 830 | out_free_disk: |
| 831 | del_gendisk(zram->disk); |
| 832 | put_disk(zram->disk); |
| 833 | out_free_queue: |
| 834 | blk_cleanup_queue(zram->queue); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 835 | out: |
| 836 | return ret; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 837 | } |
| 838 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 839 | static void destroy_device(struct zram *zram) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 840 | { |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 841 | sysfs_remove_group(&disk_to_dev(zram->disk)->kobj, |
| 842 | &zram_disk_attr_group); |
Nitin Gupta | 33863c2 | 2010-08-09 22:56:47 +0530 | [diff] [blame] | 843 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 844 | if (zram->disk) { |
| 845 | del_gendisk(zram->disk); |
| 846 | put_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 847 | } |
| 848 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 849 | if (zram->queue) |
| 850 | blk_cleanup_queue(zram->queue); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 851 | } |
| 852 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 853 | static int __init zram_init(void) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 854 | { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 855 | int ret, dev_id; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 856 | |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 857 | if (num_devices > max_num_devices) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 858 | pr_warn("Invalid value for num_devices: %u\n", |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 859 | num_devices); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 860 | ret = -EINVAL; |
| 861 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 862 | } |
| 863 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 864 | zram_major = register_blkdev(0, "zram"); |
| 865 | if (zram_major <= 0) { |
Sam Hansen | 94b8435 | 2012-06-07 16:03:47 -0700 | [diff] [blame] | 866 | pr_warn("Unable to get major number\n"); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 867 | ret = -EBUSY; |
| 868 | goto out; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 869 | } |
| 870 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 871 | /* Allocate the device array and initialize each one */ |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 872 | zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL); |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 873 | if (!zram_devices) { |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 874 | ret = -ENOMEM; |
| 875 | goto unregister; |
| 876 | } |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 877 | |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 878 | for (dev_id = 0; dev_id < num_devices; dev_id++) { |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 879 | ret = create_device(&zram_devices[dev_id], dev_id); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 880 | if (ret) |
Minchan Kim | 3bf040c | 2010-01-11 16:15:53 +0900 | [diff] [blame] | 881 | goto free_devices; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 882 | } |
| 883 | |
Davidlohr Bueso | ca3d70b | 2013-01-01 21:24:13 -0800 | [diff] [blame] | 884 | pr_info("Created %u device(s) ...\n", num_devices); |
| 885 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 886 | return 0; |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 887 | |
Minchan Kim | 3bf040c | 2010-01-11 16:15:53 +0900 | [diff] [blame] | 888 | free_devices: |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 889 | while (dev_id) |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 890 | destroy_device(&zram_devices[--dev_id]); |
| 891 | kfree(zram_devices); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 892 | unregister: |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 893 | unregister_blkdev(zram_major, "zram"); |
Nitin Gupta | de1a21a | 2010-01-28 21:13:40 +0530 | [diff] [blame] | 894 | out: |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 895 | return ret; |
| 896 | } |
| 897 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 898 | static void __exit zram_exit(void) |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 899 | { |
| 900 | int i; |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 901 | struct zram *zram; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 902 | |
Nitin Gupta | 5fa5a90 | 2012-02-12 23:04:45 -0500 | [diff] [blame] | 903 | for (i = 0; i < num_devices; i++) { |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 904 | zram = &zram_devices[i]; |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 905 | |
Jiang Liu | 6030ea9 | 2013-06-07 00:07:22 +0800 | [diff] [blame] | 906 | get_disk(zram->disk); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 907 | destroy_device(zram); |
Minchan Kim | 0231c40 | 2013-01-30 11:41:40 +0900 | [diff] [blame] | 908 | zram_reset_device(zram); |
Jiang Liu | 6030ea9 | 2013-06-07 00:07:22 +0800 | [diff] [blame] | 909 | put_disk(zram->disk); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 910 | } |
| 911 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 912 | unregister_blkdev(zram_major, "zram"); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 913 | |
Noah Watkins | 43801f6 | 2011-07-20 17:05:57 -0600 | [diff] [blame] | 914 | kfree(zram_devices); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 915 | pr_debug("Cleanup done!\n"); |
| 916 | } |
| 917 | |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 918 | module_init(zram_init); |
| 919 | module_exit(zram_exit); |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 920 | |
Sergey Senozhatsky | 9b3bb7a | 2013-06-22 03:21:18 +0300 | [diff] [blame] | 921 | module_param(num_devices, uint, 0); |
| 922 | MODULE_PARM_DESC(num_devices, "Number of zram devices"); |
| 923 | |
Nitin Gupta | 306b0c9 | 2009-09-22 10:26:53 +0530 | [diff] [blame] | 924 | MODULE_LICENSE("Dual BSD/GPL"); |
| 925 | MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>"); |
Nitin Gupta | f1e3cff | 2010-06-01 13:31:25 +0530 | [diff] [blame] | 926 | MODULE_DESCRIPTION("Compressed RAM Block Device"); |
Konrad Rzeszutek Wilk | c70bda9 | 2013-07-12 14:20:52 -0400 | [diff] [blame] | 927 | MODULE_ALIAS("devname:zram"); |